Capability for ozone high-precision retrieval on JEM/SMILES observation

We estimate the capability of ozone (O 3) retrieval with the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) instrument attached to the Exposed Facility of the Japanese Experiment Module (JEM) on the International Space Station (ISS). SMILES carries a 4-K mechanical refrigerator to cool superconducting devices in space. Since SMILES has high sensitivity thanks to the superconducting receiver, it is expected that SMILES has ability to retrieve O 3 profiles more precisely than the previous millimeter–submillimeter limb measurements from satellites. We examine the random error and the systematic error of O 3 vertical profiles based on the launch-ready retrieval algorithm developed for SMILES. The best random error with single-scan spectra is 0.4% at an altitude of 30 km with 3 km vertical resolution in the mid-latitudes. The random error is better than 5% in the altitude region from 15 to 70 km in the nighttime and from 15 to 55 km in the daytime with 3 km vertical resolution in the mid-latitudes. By averaging ten profiles, the random error is improved to 1% at 70 km altitude in the nighttime and to 5% in the daytime. Using SMILES, we expect to determine the diurnal variation of O 3 vertical profiles with high precision in the upper stratosphere. Finally, the retrieval capability of O 3 in the lower stratosphere is estimated. When retrieving spectral data using two receiver bands (624.32–626.32 GHz and 649.12–650.32 GHz) the random error above 13 km in the mid-latitudes and above 15 km in the tropics is expected to be better than 5% under clear sky conditions.